We have developed a high-throughput laser marking system using a programmable multi-spot modulated line beam capable of >13x throughput enhancement over a single-spot system. While commercially available lasers have been rapidly growing in output energy and power, single-spot marking systems cannot take full advantage of higher laser outputs without causing damage to the material. This system provides high throughput, high resolution marking on a variety of surfaces including stainless steel and polymer. This high productivity system is enabled by a high-power MEMS spatial light modulator called the Planar Light Valve (PLVTM). The PLV is a 1088-pixel device in a linear configuration supporting up to 200 kHz modulation. The PLV supports pulse energies of 920 μJ with pulse widths down to 200 femtoseconds and CW power of 1 kW at wavelengths of 355-1070 nm. In this system the PLV is imaged onto the work surface to create roughly 100 segments which are individually addressed to select the laser fluence in each spot with grayscale control. The linear array is scanned across the media using precision X-Y stages. The resulting feature size is 20 μm yielding high resolution 1270 dpi images. Each spot on the work surface is made up of several PLV pixels, which allows precise edge placements. In this demonstration a 100 W laser is used for a 13x throughput enhancement over a single-spot system with 4x better resolution. This optical system can be adapted for many laser processing applications such as additive manufacturing, lithography, and micromachining.
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